Apparatus for processing radiation detection devices



April 3, 1956 M. N. FAIRBSANK APPARATUS FOR PROCESSING RADIATION DETECTION DEVICES Filed April 5 1951 2 Sheets-Sheet l FIG.

FIG. 2

R O T N E V N April 3, 1956 M. N. FAIRBANK APPARATUS FOR PROCESSING RADIATION DETECTlON DEVICES 2 Sheets-Sheet Filed April 5, 1951 FIG. 5

FIG. 4

INVENTQR United States Patent APPARATUS FOR PROCESSING RADIATION DETECTION DEVICES 6 Claims. (Cl. 250-68) Mass, assignor to Polaroid Mass, a corporation of Dela- This invention relates to apparatus for processing radiation-sensitive products in the nature of dosimeters of the character which utilize photosensitive materials for detecting, indicating, recording and measuring such radiation.

One embodiment of dosimeter which is particularly adapted for processing by the devices set .forth herein makes use of a releasably sealed envelope which carries within its interior photographic materials, including a photosensitive element, and a rupturable container holding a photographic processing composition. The Wall members of the envelope are substantially impervious to actinic light, liquid and vapor but are formed of materials which will transmit the nuclear radiation to be detected. Processing of a dosimeter of this character is eifected by the application of pressure to opposite sides of the envelope in a manner to elfect the rupture of the container therein and the appropriate spreading of its discharged liquid within the envelope.

An object of the invention is to provide a simple, inexpensive and lightweight dosimeter processing apparatus or device making use of a pair of pressure-applying members adapted to engage a dosimeter therebetween and to apply pressure to the opposite sides of the dosimeter envelope to eifect the rupture of a container holding a liquid and located within the envelope and to spread its liquid content upon pulling the engaged envelope through the pressure-applying members, and particularly to a process ing device which is especially constructed to permit easy separation of said pressure-applying members for insertion of a dosimeter therebetween so as to carry out a processing operation.

Other objects of the invention are to provide a dosimeter processing device having a base plate, a pressureapplying member fixedly carried by the base plate, a secondpressure-applying member carried by the base plate and spring-urged for contact with the first pressure-applying member whereby to permit pressure engagement of a dosimeter envelope between the pressure applying members, and means for separating said pressure-applying members and associated with the spring means which urge said pressure-applying members together; and to provide a processing device of the character described wherein the means for separating the pressure-applying members is a manually operable, movable member connected to the spring-loaded pressure-applying member.

Other objects of the invention will inpart be obvious and will in part appear hereinafter.

The invention acordingly comprises the apparatus possessing the features, properties and the relation of components which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims. i

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings wherein:

Figure 1 is a plan view of a preferred embodiment of a '2 dosimeter processing device which forms the subject matter of this invention;

Fig. 2 is a sectional elevation on the line 2-2 of Fig. 1;

Fig. 3 is a perspective view of another embodiment of processessing device;

Fig. 4 is a plan view of an envelope dosimeter of the type with which the processing devices of Figs. 1 and 3 are usable; and

Fig. 5 is a sectional elevation taken on the line 5- 5 of Fig. 4.

While the present invention is unconcerned with radiation detection devices per se, it is nevertheless believed that a description of the construction or a dosimeter will assist in understanding the nature, operation and utility of the processing devices disclosed in Figs. 1 through 3 of the drawings. One embodiment of dosimeter which is particularly adapted for processing by the apparatus set forth herein is indicated by the general reference numeral 40 in Figs. 4 and 5 and comprises an envelope formed of outer wall members 41 and 42 which are releasably secured together, by means of a strippable adhesive bond, along the longitudinal edges thereof and also transversely of the wall members at one end thereof, as well as at a position preferably, although not necessarily, somewhat removed from the other end. This bond is adapted to provide a seal between the layers which. is impervious to liquid and to light of a wavelength actinic to photosensitive materials within the envelope 40 and is shown in Fig. 4 by the reference numeral 43 as extending over an area lying between the rectangular marginal outline of the envelope as therein illustrated and the dotted line parallel to said outline. By this arrangement it will be apparent that each layer 41 and 42 providing a wall member will have a portion at one end which is unconnected to the other Wall member. These portions 48 and 49, in the form of extensions, are in fact leaders which provide means to facilitate handling of the photosensitive unit, as well as means to assist in stripping the layers so that they may be placed in spread-apart condition after processing.

The envelope wall members 41 and 42 are each formed of a sheet material which is substantially impervious to actinic light, liquids and vapor, while being capable of transmitting nuclear radiation tobe detected, i. e., shorter wavelength radiation including X-rays and gamma rays.

A print-carrying element 45, a rupturable container 47 for a liquid processing composition, and a photosensitive element 44 are located within the interior of the envelope and are suitably secured to the inner surfaces of the Wall-members 41 and 42, as shown in Fig. 5. Photosensitive element 44 comprises one or more strips of a photosensitive material, such as silver halide, while the printcarrying element 45 may comprise a suitable sheet material, such as baryta paper. in the arrangement shown, the print-carrying element 45 is in superposed relation with a portion of the photo-sensitive element 44, while container 47 is located adjacent the end of the print-carrying element 45 which is positioned the nearest to the leader means of the dosimeter envelope.

A substantially liquid impervious sheet material, simi lar to that used for forming the envelope wall members 4-1 and 42, is employed for container 47 whereby the container is adapted to hold a processing liquid. One example of a processing liquid usable for carrying out a silver halide transfer process comprises a silver halide developer and a silver halide fixer, both in solution in the liquid. The container 47 is positioned to extend transversely of the print-carrying element 45 and is pro vided With a rupturable seal adjacent the print-carrying element whereby pressure applied to opposite sides of the dosimeter envelope will efiect the rupture of this seal and the discharge of the liquid content of the container for spreading between and in contact with the superposed print-carrying element 45 and the photosensitive element 44.

Dosimeters of the character illustrated in Figs. 4 and 5 are intended to utilize a photographic transfer process in determining the extent to which the dosimeter has been acted upon by nuclear radiation of the type to be detected. As previously pointed out, the nuclear radiation to be detected will penetrate through the envelope. Radiation of this character will form latent image in the photosensitive materials of the photosensitive element 44. The processing liquid, when spread between and in contact with the print'carrying element and the photosensitive element, is adapted to develop latent image in the photosensitive element to silver and to form, by transfer, a reverse print thereof on the print-carrying element. Following formation of the reverse image, the envelope layers are peeled or stripped apart. T he density of the transfer image is utilized to determine the extent of radiation dosage receivedby the dosimeter by comparing this density with a standard which is representative of print densities obtained by exposing photosensitive materials similar to those employed in the dosimeter to predetermined dosages of nuclear radiation.

The principles of a transfer process, as well as film structures and dosimeters suitable for use in the invention, are set forth in United States Patent No. 2,543,181., issued February 27, 1951, to Edwin H. Land for Photographic Product Comprising a Rupturable Container Carrying a Photographic Processing Liquid, copending application Serial No. 652,612, filed March 7, 1946, by Edwin H. Land for Fluid Containers, now Patent No. 2,634,886, and copending application Serial No. 218,042, filed March 28, 1951, by Murry N. Fairbank and William A. Shurcliff for Radiation Detection Devices. The last-noted application is specific to dosimeter constructions of the general nature of the dosimeter illustrated in Figs. 4 and 5 herein. Patent No. 2,543,181 and said copending applications include detailed descriptions of film units comprising a photosensitive element and a print-carrying element which are adapted to contain all of the photographic materials needed to process the unit. Also, the just-mentioned patent and copending applications are detailed as to containers for holding processing materials and further include descriptions of liquid proc essing compositions usable with such units. The practices, photographic materials and compositions described in said Patent No. 2,543,181 and said copending applications are generally suitable for carrying out the present invention and special reference to the details thereof are made in said patent and copending applications.

The dosimeters described herein are intended to be I carried on the person and to be processed at the instant the possessor of the device wishes to determine if he has been subjected to unsafe radiation conditions. Consequently, the dosimeters are relatively small. For example, the complete envelope in any of the embodiments heretofore disclosed may have dimensions of about three inches by one inch or even smaller.

Under the just-noted circumstances wherein the dosimeter is literally intended to the processed at an instants notice, it is desirable to provide processing means of simple and lightweight construction for association with the dosimeter. Preferably, the processing apparatus or device should be of a size and weight such that it may be carried on the person, as by attachment to an article of clothing, or by suspension around the neck from a ribbon or cord as in the case of the so-called military dog tag, or even carried in a pocket.

One embodiment of apparatus for processing a dosimeter of the character described is generally indicated in Figs. 1 and 2 by the reference numeral 11) and makes use of the base plate 11 having sides 12 extending upwardly therefrom. Base plate 11 may be formed of metal and the sides 12 may be formed by bending the 4 metal sheet of the base plate. The width of the base plate between the side walls is slightly greater than the width of the dosimeter envelope to be processed.

Each side wall 12 extends from adjacent one end of the base plate to a position beyond the other end thereof. Carried by the base plate, as for example by being supported from the side walls thereof, is a spreader or pressure-applying member 14. The spreader member 14 is in the form of a round rod which is suitably secured to each side wall adjacent one end of the walls by fastening means, such as screws or the like, indicated at 15. The spreader member or pressure-applying member 14 extends transversely of the base plate 11 and is located or spaced a distance above the surface of the base plate. A second spreader or pressure-applying member is indicated at 19 and is a curved or rounded portion of a flat spring 16 which has one end thereof bent over upon itself and secured to the upper surface of the base plate as by means of rivets 18 or other suitable fastening. The spring 16 is relatively wide, being almost as wide as the base plate, and has an extension 20 thereon which is bent downwardly towards the base plate. Extension 2i), as may be noted, protrudes beyond the end of the walls 12 adjacent the spreader unit. The spring element 16 is constructed of any suitable spring material and, as may be noted, is arranged so that it is constantly urged upwardly from the base plate and into contact with the spreader or pressure-applying member 14. At the same time, it will be noted that the spring 16 is movable toward and away from the base plate due to its construction and mounting.

Base plate 11 is provided at the end thereof adjacent the spreader unit with an extension 21 which under lies the extension 20 of the spring 16. The two extension portions 29 and 21 together provide means for separating the spreader members 14 and 19. Thus, the exten sion portions 20 and 21 are in effect gripper members which may be gripped between the fingers and moved relative to each other by depressing the extension 20 whereby the spreader member 19 is moved away from the spreader member 14.

As is particularly well shown in Fig. 1, each wall member 12 extends beyond the base plate at the end thereof furthest from the spreader unit. Also, each extending end of each wall member, as indicated at 22, is bent outwardly or away from the base plate. These extensions 22, which are flared outwardly, provide means which facilitate holding the processing device for carrying out a processing operation on a dosimeter inserted between the spreader members.

As previously pointed out, the type of dosimeter intended to be processed by a processing device such as that shown in the drawings is relatively small. Therefore, the processing unit itself will be small and is preferably formed of lightweight material, such as aluminum, whereby to facilitate the carrying of the device upon the person. In this latter regard, a hole 23 is formed in the base plate 11 for the reception of a carrying ribbon, cord, chain or the like. As may be observed, spring 16 is provided with a hole 24 therethrough to give access for heading rivet 18.

Operation of the processing device 10 is as follows. The processing device 10 is held in one hand and the fingers are utilized to grasp the extension portion 20 on the spring 16 and the extension portion 21 on the base plate 11 and to move the spring toward the extension 21 to free the spreader portion 19 on the spring 16 from contact with the fixed spreader member 14. This permits one to hold a dosimeter 40 by its leader portions and to insert the dosimeter between the spring spreader member 16 and the rod spreader member 14 while positioning it between the spreader members so that the leader portions extend free of the processing device. circumstances, the leader portions will extend to the right Under these:

of the spreader members and the container 47 will be located just to the left .of the spreader members. The dosimeter will be retained in the processing apparatus in the manner just described upon release of the extensions 20 and 21.

Processing now continues by grasping the processing device in one hand in such a manner that the side extensions 22 are tightly gripped and by then utilizing the other hand to grasp the leader portions of the dosimeter 40, which has been inserted into the processing device. Holding the processing device in this manner, a strong steady pull is exerted on the leader portions of the dosimeter whereby to pull the dosimeter entirely through the spreader members 14 and 19 Spreader members 14 and 19 exert a sufiicient pressure to rupture the container 47 as the dosimeter is drawn through the spreaders and to cause discharge of the liquid content of the container and he spreading thereof between the print-carrying ele-,

ment 45 and the photosensitive element 44 whereby to effect processing of the dosimeter.

After about a minute the image-forming reactions carried on within the envelope resulting from the rupture of the container and the spreading of its contents are completed. Following this, the dosimeter is peeled apart by grasping the unattached leader portions, one in each hand, and by pulling gently on the unit. An indication or record of the extent to which a person has been submitted to radiation dosage is formed as a transfer print on the printcarrying element of the dosimeter and the silver density thereof is compared with known densities which indicate this extent of radiation dosage.

Another embodiment of a processing device is shown in Fig. 3 and indicated generally by the reference numeral 36. The processing device 30, like the processing device It), makes use of a base plate portion 31 which supports a first spreader member 34 and a movable spreader member 39. Spreader member 39 is carried by a frame member comprising a pair of spaced-apart pivot arms 37, the free ends of which are fixed to the spreader or pressure-applying member 39 at opposite ends of the latter. Frame 38 is provided with an ear on each arm 37 to permit it to be pivotally secured to the base plate 31 along the e ges of the plate by means of a pivot pin or the like, as shown in Fig. 3.

A portion 50 provides an extension on each arm 37 which extends from the pivot for the frame toward the end of the base plate furthest removed from the spreader members. A crosspiece 51, joined to the ends of said extensions 50, completes the frame 38. It is to be noted that the extension portions 50 of the pivot arms are bent upwardly from the surface of the base plate 31. It will be apparent from this disclosure that the frame 38 provides means formoving the pressure-applying member 39 toward and away from the pressure-applying member 3 separation of the pressure-applying members being accomplished by pressing downwardly upon the crosspiece 51.

Coil springs 36, supported upon the base plate 31 as by having one of their ends fixed to the spreader member 34, are also connected to the spreader member 39 whereby to spring-load the spreader member 39 and constantly urge it toward contact with the spreader member 34. Two coil springs 36 are disclosed and are located at opposite ends of the spreader members. Both the spreader members 34 and 39 may have suitably rounded surfaces for contact with each other and in fact may be constructed from round rod stock.

While pressure-applying or spreader means have been shown which make use of a member having a rounded surface or which make use of a round rod or any combination of these elements, it will be appreciated that a variety of devices may be employed for this purpose. For example, in addition to the spreader means disclosed, pressure-applying members may be employed which comprise a pair of nonrotatable bars or a pair of plates, or the combination of a plate and a bar, or a pair of jawshaped members, or a plate and a roller, or a pair of pressure or pinch rolls.

From the foregoing, it will be appreciated that the aims and objects of this invention have been accomplished in the provision of means for processing dosimeters which are of simple design and which permit quick processing to be carried out at an instants notice, while at the same time the apparatus disclosed herein is of convenient lightweight construction which facilitates carriage on the person.

Since certain changes may be made in the above apparatus without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. A device for intercepting, responding to and giving a visible indication of radiation to which the user thereof has been exposed, said device comprising a dosimeter and means for mounting said dosimeter and processing the same, said dosimeter comprising an elongated envelope and carried within said envelope at least a rupturable container holding a processing liquid and a photosensitive element, the walls of said envelope being opaque to at least so much of the visible spectrum as is actinic to said photosensitive element and being transparent at least in part to said radiation, said dosimeter carrying photosensitive reagents in suflicient quantity to produce a visible record of the exposure of the photosensitive element and said container being so located relative to said photosensitive element as to be capable of releasing its liquid to permeate said element, said liquid, when released from said container, rendering said reagents effective to form said visible record, said envelope including leader means, said mounting and processing means comprising a base plate providing means for supporting said dosimeter, a pair of pressure-applying members supported by said base plate adjacent one end thereof and extending transversely of said base plate, said dosimeter being engageable by and movable between said pressureapplying members and when supported on said base plate having the leader means thereof extending through and engaged by said pressure-applying members whereby said dosimeter is movable between said pressure-applying members by exerting a pulling force on the leader means of the dosimeter, said pressure-applying members providing means upon drawing the dosimeter therebetween for rupturing said container and releasing the contents thereof to permeate the photosensitive element and to form in said dosimeter a visible record of the extent of the photoexposure of the photosensitive element, said pressure-applying members being mounted in general overlying relation to each other and a first one of said pressure-applying members being mounted for movement toward and away from the second-applying member, spring means carried by said base plate and operatively connected to said movable and first pressure-applying member for urging said movable pressure-applying member into contact with said second pressure-applying member, and manually operated means movable toward and away from said base plate and connected to said movable pressure-applying member and actuatable for effecting the separation of said pressure-applying members, said spring means being so formed and shaped as to predeterminedly load said means for rupturing said container and to substantially constantly urge said movable pressure-applying member toward said second pressureapplying member by a force of predetermined magnitude, said manually operated means having a. portion which is located in overlying relation to one end of said base plate and which is contactable by a finger of the hand for the exertion thereon of pressure sufiicient to overcome the resistance of said spring means and to move said manually operated means from a position wherein it is furthest removed from said base plate toward said base plate to effect the movement of said movable pressure-applying member away from said second pressureapplying member whereby to permit said dosimeter to be supportedly mounted on said base plate with the leader means of the dosimeter extending between 'said pressure-applying members for carrying out the processing of said dosimeter, said spring means also functioning to urge said manually operated means into its position furthest removed from said base plate and to restore said manually operated means to said position upon release of pressure upon said manually operated means.

2. In apparatus for at least processing a photosensitive dosimeter of the type having at least a photosensitive element and a rupturable container holding a liquid processing composition located relative to each other so that liquid discharged from said container may be spread over said photosensitive element, and wherein said photosensitive element and said container are carried in an elongated envelope provided with leader means extending from one end thereof to assist in handling and processing said dosimeter, in combination, a base plate providing a dosimeter support, and pressure-applying means so engageable with the leader means of a dosimeter mounted on said support as to have an end portion of said leader means extend therethrough, said dosimeter being movable through said pressure-applying means and said pressure-applying means being capable of applying sufficient pressure to the opposite sides of said dosimeter to effect the rupture of the container therein and the discharge of its liquid content within said envelope upon drawing said dosirneter through said pressure-applying means by pulling upon said end portion of said leader means, said pressure-applying means comprising a first pressure-applying member supported by said base plate adjacent one end thereof and extending transversely of said base plate at a position elevated above the surface of the base plate, an elongated and generally fiatspring, said spring being fixed near one end thereof to said base plate and having a rounded portion near the free end thereof and providing a second pressure-applying member, said spring, including said rounded portion, having a width dimension which extends transversely of said base plate and being so shaped and mounted relative to said first pressure-applying member as to constantly urge the rounded portion thereof, which provides the second pressure-applying member, into contact with said first pressure-applying member by a force of predetermined magnitude whereby said pressure-applying means are sub jected to asubstantially constant and uniform loading, and means for manually separating said spring and its rounded pressure-applying member from said first pressure-applying member whereby to permit a dosimeter to be mounted on said base plate with the end portion of said leader means extending between and through said pressure-applying means for carrying out the processing of said dosimeter, said means for manually separating said spring and said second pressure-applying member from said first pressure-applying member comprising an extension portion on said spring located between the rounded portion and the free end of the spring.

3. in apparatus for at least processing a photosensitive dosimeter of the type having at least a photosensitive element and a rupturable container holding a liquid processing composition located relative to each other so that liquid discharged from said container may be spread over said photosensitive element, and wherein said photosensitive element and said container are carried in an elongated envelope provided with leader means at one end thereof to assist in handling and processing said dosimeter, in combination, a base plate providing a dosimeter support, a pair of wall members extending longitudinally of said base plate, each said wall member extending along a side of said base plate, mechanism carried by said base plate for processing a dosimeter supported on said base plate and said mechanism including pressure-applying means for applying suflicient pressure to the opposite sides of said dosimeter to effect the rupture of the container therein and the spreading of its liquid content within said envelope by pulling said dosimeter through and between said pressure-applying means, said dosimeter being supported upon said base plate with an end portion of said leader means engaged between said pressure-applying means and extending therethrough for effecting the movement of the dosimeter through said pressure-applying means by pulling upon said end portion of said leader means, said pressure-applying means comprising a first pressure-applying member having a rounded surface and positioned between said wall members at one end of said base plate and secured to said wall members at a location elevated above the surface of said base plate, an elongated and generally flat spring fixed near one end thereof to said base plate and extending longitudinally of said base plate and between the wall members thereof in underlying relation to said first pressure-applying member, said spring being formed with a rounded portion providing a second pressure-applying member which is located in underlying relation to said first pressure-applying member and said spring being so formed and shaped as to predeterminedly load said pressure-applying means and to substantially constantly urge said second pressure-applying member toward said first pressure-applying member by a force of predetermined magnitude, and means provided by said Wall members for manually grasping and holding the processing device for carrying out the processing of a dosimeter inserted between said pressure-applying members, said means for grasping and holding the processing device comprising an extension of each said wall member whereby each said wall member extends beyond said base plate at the end thereof furthest removed from said pressure-applying members, said extensions on the ends of said wall members being flared away from each other and outwardly of said base plate.

4. A device as defined in claim 2 wherein said base plate, at the end thereof adjacent said pressure-applying members, is provided with an extension positioned to underlie the extension portion on said spring and providing means used in conjunction with said extension portion on said spring for manually separating said pressure-applying members.

5. A device as defined in claim 3 wherein said spring extends beyond the rounded pressure-applying member to provide an extension adapted to be manually pressed towards the base plate for separating said pressure-applying members and wherein said base plate, at the end thereof adjacent said pressure-applying members, is provided with an extension which underlies the extension on said spring and which is manually engageable simultaneously with the extension portion of said spring where by to assist in applying pressure to said spring to move the spring toward the base plate.

6. In apparatus for at least processing a photosensitive dosimeter of the type having at least a photosensitive element and a rupturable container holding a liquid processing composition located relative to each other so that liqiud' discharged from said container may be spread over said photosensitive element, and wherein said photosensitive element and said container are carried in an elongated envelope provided with leader means at one end thereof to assist in handling and processing said dosimeter, in combination, a base plate providing a dosimeter support, mechanism carried by said base plate for processing a dosimeter supported on said base plate and said mechanism including pressure-applying means which are under a substantially constant predetermined loading for applying, to the opposite sides of said dosimeter, pressure of a predetermined magnitude sufficient to elfect the rupture of the container therein and the spreading of its liquid content within said envelope by pulling said dosimeter through and between said pressure-applying means, said dosimeter being supported upon said base plate with an end portion of said leader means engaged between said pressure-applying means and extending therethrough for effecting the movement of the dosimeter through said pressureapplying means by pulling upon said end portion of said leader means, said pressure-applying means comprising a first pressureapplying member supported on the surface of said base plate to extend transversely thereof at a location adjacent one end of the base plate, a second pressureapplying member, means for mounting said second pressure-applying member in superposed relation to said first-mentioned pressure-applying member, said mounting means including a frame pivoted to said base plate and having a pair of spaced-apart pivot arms which are respectively secured to said second pressure-applying member at opposite ends thereof, each said pivot arm having an extension portion extending from its pivot toward the end of the base plate furthest removed from said pressure-applying members, and spring means supported on said base plate and connected to said second pressureapplying member for constantly urging said second pressure-applying member into contact with said first pressure-applying member and creating said predetermined loading of said pressure-applying means, said extension portions on said pivot arms providing means for rocking said pivot arms about their pivot whereby to move said second pressure-applying member away from said first pressure-applying member.

References Cited in the file of this patent UNITED STATES PATENTS 34,515 McCoy Feb. 25, 1862 163,170 Entrekin May 11, 1875 312,337 Dorey Feb. 17, 1885 2,477,304 Land July 26, 1949 2,483,014 Land Sept. 27, 1949 2,659,825 Land Nov. 17, 1953 FOREIGN PATENTS 679,963 Germany Aug. 19, 1939 France June 23, 1931 

1. A DEVICE FOR INTERCEPTING, RESPONDING TO AND GIVE A VISIBLE INDICATION OF RADIATION TO WHICH THE USER THEREOF HAS BEEN EXPOSED, SAID DEVICE COMPRISING A DOSIMETER AND MEANS FOR MOUNTING KSAID DOSIMETER AND PROCESSING THE SAME, SAID DOSIMETER COMPRISING AN ELONGATED ENVELOPE AND CARRIED WITHIN SAID ENVELOPE AT LEAST A RUPTURABLE CONTAINER HOLDING A PROCESSING LIQUID AND A PHOTO SENSITIVE ELEMENT, THE WALLS OF SAID ENVELOPE BEING OPAQUE TO AT LEAST SO MUCH OF THE VISIBLE SPECTRUM AS IS ACTINIC TO SAID PHOTOSENSITIVE ELEMENT AND BEING TRANSPARENT AT LEAST IN PART TO SAID RADIATION, SAID DOSIMETER CARRYING PHOTOSENSITIVE REAGENTS IN SUFFICIENT QUANTITY TO PRODUCE A VISIBLE RECORD OF THE EXPOSURE OF THE PHOTOSENSITIVE ELEMENT AND SAID CONTAINER BEING SO LOCATED RELATIVE TO SAID PHOTOSENSITIVE ELEMENT AS TO BE CAPABLE OF RELEASING ITS LIQUID TO PERMEATE SAID ELEMENT, SAID LIQUID, WHEN RELEASED FROM SAID CONTAINER, RENDERING SAID REAGENTS EFFECTIVE TO FORM SAID VISIBLE RECORD, SAID ENVELOPE INCLUDING LEADER MEANS, SAID MOUNTING AND PROCESSING MEANS COMPRISING A BASE PLATE PROVIDING MEANS FOR SUPPORTING SAID DOSIMETER, A PAIR OF PRESSURE-APPLYING MEMBERS SUPPORTED BY SAID BASE PLATE ADJACENT ONE END THEREOF AND EXTENDING TRANSVERSELY OF SAID BASE PLATE, SAID DOSIMETER BEING ENGAGEABLE BY AND MOVABLE BETWEEN SAID PRESSUREAPPLY MEMBERS AND WHEN SUPPORTED ON SAID BASE PLATE HAVING THE LEADER MEANS THEREOF EXTENDING THROUGH AND ENGAGED BY SAID PRESSURE-APPLYING MEMBERS WHEREBY SAID DOSIMETER IS MOVABLE BETWEEN SAID PRESSURE-APPLYING MEMBERS BY EXERTING A PULLING FORCE ON THE LEADER MEANS OF THE DOSIMETER, SAID PRESSURE-APPLYING MEMBERS PROVIDING MEANS UPON DRAWING THE DOSIMETER THEREBETWEEN FOR RUPTURING SAID CONTAINER AND RELEASING THE CONTENTS THEREOF TO PERMEATE THE PHOTOSENSITIVE ELEMENT AND TO FORM IN SAID DOSIMETER A VISIBLE RECORD OF THE EXTENT OF THE PHOTOEXPOSURE OF THE PHOTOSENSITIVE ELEMENT, SAID PRESSURE-APPLYING MEMBERS BEING MOUNTED IN GENERAL OVERLYING RELATION TO EACH OTHER AND A FIRST ONE OF SAID PRESSURE-APPLYING MEMBERS BEING MOUNTED FOR MOVEMENT TOWARD AND AWAY FROM THE SECOND-APPLYING MEMBER, SPRING MEANS CARRIED BY SAID BASE PLATE AND OPERATIVELY CONNECTED TO SAID MOVABLE AND FIRST PRESSURE-APPLYING MEMBER FOR URGING SAID MOVABLE PRESSURE-APPLYING MEMBER INTO CONTACT WITH SAID SECOND PRESSURE-APPLYING MEMBER, AND MANUALLY OPERATED MEANS MOVABLE TOWARD AND AWAY FROM SAID BASE PLATE AND CONNECTED TO SAID MOVABLE PRESSURE-APPLYING MEMBER AND ACTUATABLE FOR EFFECTING THE SEPARATION OF SAID PRESSURE-APPLYING MEMBERS, SAID SPRING MEANS BEING SO FORMED AND SHAPED AS TO PREDETERMINEDLY LOAD SAID MEANS FOR RUPTURING SAID CONTAINER AND TO SUBSTANTIALLY CONSTANTLY URGE SAID MOVABLE PRESSURE-APPLYING MEMBER TOWARD SAID SECOND PRESSUREAPPLYING MEMBER BY A FORCE OF PREDETERMINED MAGNITUDE, SAID MANUALLY OPERATED MEANS HAVING A PORTION WHICH IS LOCATED IN OVERLYING TO ONE END OF SAID BASE PLATE AND WHICH IS CONTACTABLE BY A FINGER OF THE BASE FOR THE EXERTION THEREON OF PRESSURE SUFFICIENT TO OVERCOME THE RESISTANCE OF SAID SPRING MEANS AND TO MOVE SAID MANUALLY OPERATED MEANS FROM A POSITION WHEREIN IT IS FURTHEST REMOVED FROM SAID BASE TOWARD SAID BASE PLATE TO EFFECT THE MOVEMENT OF SAID MOVABLE PRESSURE-APPLYING MEMBER AWAY FROM SAID SECOND PRESSUREAPPLYING MEMBER WHEREBY TO PERMIT SAID DOSIMETER TO BY SUPPORTEDLY MOUNTED ON SAID BASE PLATE WITH THE LEADER MEANS OF THE DOSIMETER EXTENDING BETWEEN SAID PRESSURE-APPLYING MEMBERS FOR CARRYING OUT THE PROCESSING OF SAID DOSIMETER, SAID SPRING MEANS ALSO FUNCTIONING OF URGE SAID MANUALLY OPERATED MEANS INTO ITS POSITION FURTHEST REMOVED FROM SAID BASE PLATE AND TO RESTORE SAID MANUALLY OPERATED MEANS TO SAID POSITION UPON RELEASE OF PRESSURE UPON SAID MANUALLY OPERATED MEANS. 